Chemisorption binding of gold(III) from solutions with bismuth dipropyldithiocarbamate: Supramolecular self-assembly (role of the secondary Au…S and aurophilic interactions) and thermal behavior of the solvated heteropolynuclear ionic type complex ([Au{S2CN(C3H7)2}2]3[Bi2Cl9] • 0.5CO(CH3)2 • 0.5HCl) n